Sofa



FIG. 1 is a front view of the sofa;

FIG. 2 is a perspective view of the sofa;

FIG. 3 is a rear view of the sofa;

FIG. 4 is a top view of the sofa;

FIG. 5 is a left side view of the sofa, the right side being a mirror image thereof; and,

FIG. 6 is a bottom view of the sofa. 

CLAIM The ornamental design for a sofa, as shown and described. 